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• Decide on regular teleconf time
• Normalization Summary (Melinda) - Concerns regarding simulation comparisons, particularly how to scale the livetime of the different simulations, were voiced over email to a limited group. The basic conclusions of the discussion are:
  • The livetime is dependent not only on the flux value you are scaling to, but on the geometry of your generating surface with regards to your detector. After scaling, this will effect the ratio of the vertical to horizontal flux for each simulation. For example, imagine a generating sheet with surface area = A compared to one with surface area = 2A: the horizontal flux will not be same after scaling the livetime. Similarly, a generating sheet at distance = z above your detector will result in a different horizontal flux than a sheet at distance = 2z above your detector. These are important considerations, and we should either make our generation surfaces identical (as we have done for the detector), or confirm that the vertical to horizontal flux matches what is seen in nature (2:1 for an isotropic source, for example), and is not dependent on changes in the geometry.
  • Chao brought up the point that Monica's simulation assumes that particles are generated uniformly from a spherical source. Although this is true in principle, it is not representative of the source at the surface or underground. It was concluded that to first order, a horizontal sheet should be used.
  • Tasks: I suggested to Monica, Chao, and Angie that they perform their simulations with geantinos (for fast computing time), calculate their livetime, then repeat the exercise after changing a geometrical parameter in the generating surface, such as the surface area or vertical distance. Although the vertical flux is tied to the M&H value (Table I), I suspect the horizontal flux will differ in each case. If we are concerned about the vertical to horizontal flux matching nature, then a something similar to the 5-sided cube source that I presented at the November AARM meeting could be useful. If we are mostly concerned with tracking the changes between models, the fastest solution is to make our entire geometry, including generating surface, standard for all simulations.

• Discuss what's the “perfect” way to simulate the cosmogenics underground(Chao). A suggestion has been made(see chao's slides).

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